Panicum plant named ‘Red Flame’

ABSTRACT

The new and distinct cultivar of ornamental grass named  Panicum virgatum  ‘Red Flame’ with blue-green foliage that develops bright wine coloration in late summer on a large portion of the upper foliage, with upright and arching habit and dense culms producing airy panicles of burgundy, suitable as a multi-seasonal interest as a mass or specimen landscaping, potted plant, and for cut flower arrangements.

Botanical classification: Panicum virgatum.

Variety denomination: ‘Red Flame’.

STATEMENT REGARDING PRIOR DISCLOSURES UNDER 37 CFR 1.77(B)(6)

The first non-enabling information of the claimed plant was thephotograph and brief description on a website operated by WaltersGardens, Inc. on Feb. 1, 2022. The claimed plant was first sold on May16, 2022, by Walters Gardens, Inc. to Blue Sky Nursery who obtained theplant and all information relating thereto, from the inventor. No plantsof Panicum ‘Red Flame’ have been sold in this country or anywhere in theworld, nor has any disclosure of the new plant been made more than oneyear prior to the filing date of this application, and such sale ordisclosure within one year was either derived directly or indirectlyfrom the inventor.

BACKGROUND OF THE PLANT

Panicum virgatum ‘Red Flame’, hereinafter also referred by the cultivarname ‘Red Flame’ and the “new plant” is a new and distinct cultivar ofSwitchgrass. The cross was performed in the summer of 2017 by theinventor with ‘Huron Solstice’ U.S. Plant Pat. No. 21,498 as the femaleor seed parent and ‘Rostrahlbush’ (not patented) in the inventor'sgarden at Goderich, Ontario, Canada. The seed was collected by theinventors in the autumn of 2017. The single seedling was initiallyselected from among many for further observation in the summer of 2018and for final field evaluation in the fall of 2020 at a nursery inBayfield, Ontario, Canada.

The new plant has been successfully propagated by division at the samenursery in Bayfield, Ontario and later by tissue culture and found toproduce identical plants that maintain the unique characteristics of theoriginal plant in multiple generations. The plant is stable andreproduces true to type in successive generations of asexualreproduction.

BRIEF SUMMARY OF THE PLANT

Panicum virgatum ‘Red Flame’ differs from its female parent in that‘Huron Solstice’ is taller and has more upright foliage. The male parentis more upright in habit, and the fall color is more reddish purple andless bright wine-colored.

The nearest comparison varieties known to the inventors are: ‘ApacheRose’ U.S. Plant Pat. No. 29,142, ‘Cheyenne Sky’ U.S. Plant Pat. No.23,209, ‘RR1’ U.S. Plant Pat. No. 17,944, ‘Shenandoah’ (not patented),and ‘Prairie Fire’ U.S. Plant Pat. No. 19,367.

‘Apache Rose’ is much taller in habit and slightly more upright and theleaves are more blue and less flushed with burgundy. ‘Cheyenne Sky’ hasa smaller, deeper burgundy and less bright wine coloration in the latesummer color with less saturation of reddish color. ‘Shenandoah’ istaller and more upright in habit, less vigorous, with less reddishsaturation that develops later in the fall. ‘RR1’ U.S. Plant Pat. No.17,944 (more commonly known as ‘Ruby Ribbons’) is significantly shorterin habit. ‘Prairie Fire’ has a slightly taller habit, and the fallfoliage color is more greyed-purple and not as bright wine-colored. ‘RedFlame’ begins the bright wine coloration in late July and is morevigorous than all of the above-listed comparison cultivars.

The following traits of Panicum virgatum ‘Red Flame’, in combination,have been repeatedly observed in multiple generations of asexuallypropagated plants and distinguish the new plant from all other switchgrass plants known to the inventor:

-   -   1. Bluish-green foliage that develops significant bright wine        color in late summer on a large portion of the upper foliage;    -   2. Upright and arching habit with dense culms;    -   3. Airy panicles of burgundy;    -   4. Strong vigorous growth habit.

BRIEF DESCRIPTION OF THE DRAWINGS

The photographs of the new plant demonstrate the overall appearance ofthe plant, including the unique traits. The colors are as accurate asreasonably possible with color reproductions. Ambient light spectrum,source, and direction may cause the appearance of minor variations incolor.

FIG. 1 shows a two-year-old plant in a trial garden in Zeeland, Mich.inflorescence in early to mid-October.

FIG. 2 shows a cultivar comparison of one-year-old plants in a trialfield in Bayfield, Ontario, Canada, prior to flowering, with‘Shenandoah’ in the left row, ‘Rostrahlbush’ in the center, and ‘RedFlame’.

DETAILED BOTANICAL DESCRIPTION

The following descriptions and color references are based on the 2015edition of The Royal Horticultural Society Colour Chart except wherecommon dictionary terms are used. The new plant, ‘Apache Rose’, has notbeen observed in all possible environments. The phenotype may varyslightly with different environmental conditions, such as temperature,light, fertility, moisture, and maturity levels, but without any changein the genotype. The following observations and size descriptions are ofa four-year-old plant in a trial garden of a wholesale perennial nurseryin Zeeland, Mich., USA in full sun with supplemental water andfertilizer as needed.

-   Parentage: Female (seed parent) Panicum virgatum ‘Huron Solstice’ x    male (pollen patent) ‘Rotstrahlbush’;-   Propagation:-   Method: By division of the culms and sterile shoot-tip tissue    culture;    -   -   Time to finishing in a 3.8-liter pot.—About 10 weeks.        -   Rooting habit.—Normal, coarsely branching; root color            nearest RHS 155D.        -   Vigor.—Rapid.-   Plant description:-   Plant shape and habit: Hardy herbaceous perennial forming tightly    rhizomatous clump, with upright culms and arching foliage, topped    with finely textured airy panicles that are wider than tall in    maturity;-   Plant size: Foliage height at flowering is about 100 cm tall from    soil line to the top of the foliage and 120 cm tall to top of    flowers; about 35 cm wide at soil line and about 150 cm at widest    point about 90 cm above soil;-   Foliage description: Glabrous, with microscopic marginal dentations,    flat, alternate along culm, arching, sheathed from node of    attachment to ligule, linear; adaxial and abaxial surfaces dull;    deciduous but persist through winter;-   Foliage size: To about 51 cm long and about 10 mm wide, shorter    distally, with sheath portion to about 15 cm long, totally to 66 cm    long; averaging about 50 cm and 9 mm wide;-   Foliage color: Adaxial surface early season and young foliage    nearest RHS 138A; Abaxial surface early season and young foliage    between RHS 146B and RHS 146A; Adaxial surface midseason between RHS    N186C and RHS 187B in the distal one-half to five-sixths and the    proximal portion between RHS N138B and RHS 147B; Abaxial surface    midseason: between RHS 187C and RHS 187B in the distal one-half to    three-quarters, and proximally nearer the culm between RHS N138B and    RHS 147B; Adaxial late season in the distal one-half to five-sixths    between RHS N186A and RHS 187A, proximally between RHS N138B and RHS    147B; Abaxial late season in distal one-half to three-quarters    between RHS N186A and RHS 187A, proximally between RHS N138B and RHS    147B;-   Veins: Parallel; midrib about 0.7 mm across; adaxial recessed,    abaxial costate and smooth; adaxial midrib color between RHS N138B    and RHS 147B distally becoming between RHS N186A and RHS 187A,    abaxial midrib nearest RHS 138A proximally and nearest RHS 187A    distally, color of secondary veins same as the surrounding leaf on    both the top and bottom of the leaf;-   Culm (stem): Erect; terete; glabrous; glaucous proximally; dull    surface; 75% enclosed by leaf sheath; about 5 nodes per culm; about    160 per clump;-   Culm dimension: To about 56 cm long without panicle, average about    51 cm; including panicle to about 84 cm long, with average about    81.0 cm; about 3.5 mm diameter at base; internode length average    about 73 cm;-   Culm color: Nearest RHS N146D proximally, distally nearest RHS 137B;    Node description: about 5 per culm, slightly swollen to about 4 mm    diameter; color nearest RHS 197B;-   Inflorescence: Finely branched open panicle, one panicle per culm;-   Flower timing: Beginning early August, flowering through late August    and panicles dry and remain effective through winter;-   No fragrance detected;-   Panicle: Pyramidal; to about 41 cm tall and 32 cm wide; overall    effective color RHS 187A;-   Rachis: Terete, branched, glabrous, glaucous; about 58 cm long and    about 2 mm at base; branches to about 27 cm long and about 0.7 mm    diameter held at about 45 to 60 degrees angle above horizontal;    color nearest RHS 137B;-   Pedicel: Thin; terete; between 2 mm and 12 mm long and about 0.2 mm    diameter; color nearest RHS 137A with moderate blush on dorsal    portion of nearest RHS 187A;-   Rachilla: Thin; about 2 min long and 0.2 mm diameter; color nearest    RHS 137B;-   First glume: About 4 mm long and 1 mm wide; with truncate clasping    base and acute apex; color between RHS 187B and RHS 187A;-   Second glume: About 4 mm long and 2 mm wide; with truncate clasping    base and acute apex; color between RHS 187B and RHS 187A;-   Lemma:    -   -   Outer and inner.—Both about 3 mm long and 1.5 mm wide; with            truncate clasping base and acute apex; color between RHS            187B and RHS 187C on surfaces exposed to sun and between RHS            138B and RHS 145B in areas minimally exposed to sun.-   Spikelet: Usually with 2 flowers, 1.5 to 2.5 cm long and 2.5 mm    wide; flowering on rachis;-   Gynoecium:    -   -   Stigma.—Two, feathered, protruding about 1.5 mm from glume;            color nearest RHS 187A.-   Androecium:    -   -   Filaments.—Fine, hair-like, white, less than 0.1 mm diameter            and up to 2.0 mm long.-   Anthers: Two or three; dorsifixed, longitudinal; about 2.5 mm long    and about 1.0 mm wide; color nearest RHS N25A;-   Pollen: Round, less than 0.1mm in diameter; nearly transparent;    abundant; color lighter than RHS 155D;-   Fruit: Caryopsis; about 2.5 mm long and about 1.5 mm wide; color    nearest RHS 164C;-   Growth and hardiness: The plant is very drought once established.    Hardiness at least from USDA zone 4 through 9.-   Pest and disease resistance: Rust diseases such as Puccinia ssp.    have not been observed. Other disease and pest resistance beyond    what is typical of that of other Switch Grasses has not been    observed.

I claim:
 1. A new and distinct cultivar of switchgrass Panicum virgatumplant named ‘Red Flame’ as herein described and illustrated.